The Commencements of Cessations
by Thorn17
Summary: Penny and Leonard are in a relationship. Again. But then Sheldon accidentally makes a statement, the effect of which can never be retracted. What will Sheldon do now?
1. Chapter 1

I was rudely interrupted from conducting my latest work into string theory by a gentle _knock-knock _on my bedroom door. Suppressing the urge to ask the visitor to knock again - as knocking three times was part of my own routine but seemingly not theirs - I realised that it could only be Penny standing on the other side of the door as Leonard, Howard and Raj had gone out to the comic book store to buy something I'd had the foresight to pre-order. Another revealing factor was that the knock was cautious and polite, meaning that Penny wanted something. Although I was in no mood for discussing trivial topics such as waitressing or shoes, I respected the fact that she hadn't just wandered into my room like a lost sheep. Despite Leonard's protests about the ethics of using operant conditioning on his girlfriend, it was working well. The strange qualms displayed by humans of inferior intellect escaped my comprehension. However, quantum theory did not, so I turned my attention back to my work.

"Sheldon, can I come in?"

"If you must, but be quiet. I'm _working_."

The bedroom door opened and closed, allowing Penny ample time to pass through. I heard a shuffle as she approached me, and could see in the reflection of my laptop screen that she was trying to decipher what I was working on. "If you're doing more of that physics stuff, I'll come back later. I can't take any more Skinner's cat experiments right now."

With a sigh, I saved my work, pushed the laptop screen down to activate the stand-by mode, and swiveled on my chair to face her. It seemed that this was going to be a long conversation. "I'm a _physicist. _It's highly probable that I'll always be working on 'physics stuff'. And it's _Schrödinger's_ cat, Penny. B.F. Skinner was a psychologist - _not _physicist - who explored the concept of operant conditioning. That must be the twenty-third time that I've told you. Pay attention next time or get out."

"I won't be long, I just needed to ask you something." She absentmindedly sat on the edge of my bed. I bit my lip in order to refrain from commenting. I didn't mind so much when Penny did it.

"Very well, but I still _refuse_ to discuss shoes with you."

"Fine. I was just wondering, has Leonard said anything about me to you?"

"Define 'anything'. For example, Leonard has mentioned your name frequently throughout the duration of your on-off relationship, and he often refers to your ability to..."

"Sheldon! I don't want to discuss personal things like that with _you_!"

"Well you should be more specific in future. There are an infinite number of things that you could be referring to."

She rolled her eyes. "Ugh, there goes tact! I'll try this another way, explaining it in terms that there is no possibility that you can misinterpret. Let's see, during your visit to Earth from Planet Sheldon, has Leonard indicated to you that he wishes to terminate the relationship I share with him?"

"I presume that you mean 'Sheldonopolis' as I do not yet own a planet, and that you're referring to the popular slang term that Leonard wants to 'dump you'".

"Yes."

"No, Leonard has not _implied _anything."

"Well, that's good then." Relief began to flood her features, which was both unfair and premature because I had not yet finished verbalising my response.

"You misunderstand me, let me finish. Leonard simply _informed_ me of his intentions. There was no uncertainty or implying involved."

There was a short pause. I could not predict how Penny would react, but it felt good to release the guilt that had been metaphorically 'gnawing' at me. Though I probably deserved it, I hadn't slept properly since I'd eavesdropped on Leonard's conversation with Howard, thus accidentally acquiring the information. Afterwards, I'd felt compelled to challenge Leonard about it, and he had explained the situation but asked me not to tell Penny. He was trying to find 'the right way to break the news to her.' Quite frankly, Penny should at least be partly glad to be escaping the clutches of a 'physicist' whose work is becoming so derivative. Lost in my own thoughts for a second, I was mildly shocked when Penny finally spoke.

"_What?_" Her one word reply contained so many feelings and thoughts all at once: incredulity, pain and anger. It unnerved me. I didn't want to tell her because Leonard had unfairly sworn me to secrecy, but at the same time I felt duty-bound to tell Penny because she had asked me directly. I couldn't lie to her over something as serious as this.

I was unsure of the social protocol for this situation, so I simply told the truth. That was _always _the right things to do, wasn't it? At least, it's what my mother had always said. "A few days ago, he happened to mention that he wanted to 'dump you' but didn't know how to go about doing it. Although I believe that I was a last resort, he discussed his dilemma with me all the same because he was in desperate need of guidance."

"And it didn't occur to you to tell _me _any of this, Sheldon? I'm _supposed_ to be your friend!" Why was Penny angry at me? It was _Leonard_ who was about to break her heart.

"Of course you're my friend, Penny, but consider _my_ problem. Leonard asked me not to tell you, therefore if I _had _told you then I would be in violation of Clause..."

"Let me guess! It would have violated one of the clauses in your stupid Roommate Agreement!" Her anger unnerved me. I didn't like people arguing. A good debate was fine, but arguments involved too many emotions and unresolved issues, and consequently always ended badly.

"Words cannot express how refreshing it is for me to see that you understand something after only hearing it once." Though it was originally only intended to be an intelligent-but-witty answer, my retort seemed to exhibit some characteristics of sarcasm. However, as Penny had failed to both challenge my remark within her usual response time _or_ question my tentative use of sarcasm, I turned my attention back to rebooting my laptop and continuing my string theory work.

"What did I do wrong, Sheldon?" The pain in Penny's voice as her whispered question broke the silence alarmed me. Rather than confusion and sadness, I'd expected the anger and feistiness that was typical of my Penny. Before this conversation began, I could have counted the number of times that Penny had surprised me on my hands. This was no longer the case. I would either need a third hand to continue counting, or would have to resort to using other extremities, such as my toes. Her words lingered in the air, and I began to feel uncomfortable. It was rare that I did not have an answer, albeit an unlikely or childish one, and consequently concentrated on realising that my heart rate had accelerated and a sickly butterfly feeling had appeared in my stomach. Thankfully, the seriousness of these problems was likely to be minute and therefore easily dismissible, as I knew that these were common symptoms of being nervous. Nerves seemed a more likely explanation in this unfamiliar scenario, rather than a specific anxiety disorder or fear.

"I sense that it would be more appropriate for you to speak to Leonard about this, because there is no possible way that _I_ could answer that question. Might I suggest that you go and find him in the comic book store and ask _him _rather than me? However, I'd be very grateful if you pretended that it wasn't me that had told you."

"Don't worry, Sheldon, that's what I'm planning on doing! I'm sorry for being mad with you earlier, and I won't tell him that I've found out through your inability to remember instructions before relaying details of the conversation. Leonard should never have put you in that situation in the first place! Oh, and thanks for the tip-off!" Penny cried, leaping off my bed and slamming the door behind her as she left the room in what I could only assume was a journey to confront Leonard. Thankfully, the vibrations that had originated from Penny's new violent door-shutting technique had not dislodged or knocked over any of my collectibles, even missing the comic book stack that I had re-organised yesterday. With the slam of the door still echoing around my head, I resumed my work on string theory again for what seemed like the umpteenth time in a few minutes.

It was only when I lay in bed that night, having locked my door to prevent an angry Leonard smothering me in the middle of the night, that I realised that earlier I had mentally referred to Penny as '_my_ Penny.' I tried to blame this irregularity on tiredness - as this reflection was occurring way past my normal bedtime - but somewhere deep down inside, some little voice was telling me that I was wrong. Instead of exhaustion, I - Sheldon Lee Cooper, PhD - was experiencing what has been defined in the dictionary as 'love.'

Oh, how I wished that this was a 'bazinga' moment! But alas, it was not to be.


	2. Chapter 2

I am led to believe that the appropriate term to use in order to describe breakfast with Leonard the following morning would be 'awkward.' Penny and Leonard's confrontation last night had reminded me of my childhood back in Texas, with my mother and father constantly yelling at each other from dusk till dawn. Unlike the last time I had eavesdropped on a conversation, nothing I had heard had made me experience guilt, confusion, anger or sadness. It was quite simple: Penny had ended her relationship with Leonard before he had the chance to. Though Penny was true to her word, and my name was never mentioned in their 'conversation', _I_ knew that _Leonard_ knew that it was _I_ who had told Penny of his intentions, and that was how_ she_ knew. However, Leonard _didn't _know that _I _knew that _he _knew that _I _had told Penny. He probably wouldn't be able to keep up with that even if I explained it to him.

My day had already been ruined when the need to have an early bowel movement interrupted my routine. I liked routines. Things happened as they should, _when _they should. It didn't take somebody as intelligent as I to know that nothing would happen as it should today. As I poured myself a bowl of cereal with medium fibre content, I was alerted to Leonard's presence on the sofa as he began to stir from his slumber. It appeared that he had not adjourned to bed last night.

"Good morning."

"Is it?" Leonard retorted, shielding his eyes from the daylight. Something changed in his facial expression as he spoke. I didn't know what it was though, I needed more information before I could hypothesise.

"How are you today?" I asked, in order to fulfill an obligation to ask Leonard how he was feeling at least once every day, even if I didn't care.

"Why, is there any reason that I _shouldn't_ be okay?"

"Just asking. It's social protocol." I had no patience to wait for a response. "What are you doing today?"

"I think a better question would be 'what did you do _yesterday_, Sheldon?'" There was something different in Leonard's voice. The pitch was a little higher than normal, and he emphasised my name as if I did not know that it was mine.

"Oh, nothing much. I simply continued my latest work into string theory and quantum physics because, as you know, I am a theoretical physicist."

"Yeah, I knew _that_," he said. Having shared an apartment with Leonard for a few years now, I believed that I was adept at interpreting his facial expressions. The one currently being displayed was irritation. Well, either irritation or constipation. I could never be too sure, because even though he had frequently ridiculed my practice of ordering cereals by their fibre content, I suspected that he used my system in times of trouble. Unfortunately, I had not been able to collect enough data and evidence in order to either prove or disprove my theory, and so a constipated Leonard remained a valid diagnosis in my mind. "I knew that, Sheldon. I also know something _else_."

"You only know _one_ other thing besides the fact that my occupation is a theoretical physicist? I was aware that your intelligence is lower than mine, but really Leonard, that is quite shocking."

"Are you trying to make a _joke_?"

Honestly, there was no need for him to sound so incredulous. "Yes, it's an experiment. I wanted to see if it would help to relieve the present atmosphere that I believe could be aptly relieved by following the actions within the idiom 'cut the atmosphere with a knife.'"

"Whatever," said an exasperated Leonard. "I know something that you _don't _know."

"Unlikely, but continue."

"There's no way that you could _possibly _know this piece of information."

"Again, unlikely. Don't think that you're at an advantage here, Leonard. With my eidetic memory, I could recall a piece of information that I read once many years ago as clearly as if it were yesterday."

"Don't worry, Sheldon. You don't have to trawl through years of memories to recall this _particular_ piece of information. You only learnt it a little while ago, and so your recollection should be quite clear."

"I'm sure it will be," I answered. "Well, what _is _this piece of information?"

"I had no need to worry about entrusting a secret to somebody that I _thought_ was my friend. Everything went swimmingly yesterday, just as I'd planned." There was a pause. I presumed he was waiting for a response, so I offered one.

"Is that sarcasm?"

"Yes! Well done, Sheldon!"

"Was _that _sarcasm too?"

"Stop it, Sheldon! Penny _dumped _me last night because she found out that _I _was planning to end our relationship, and she wanted to beat me to it!"

"So?"

"What do you mean '_so_?'"

"Well, you wanted the relationship to end, and it has. This was always the inevitable conclusion, so I don't understand what your problem is."

"My _problem_, Sheldon, is that you told her what I was going to do! You betrayed my trust. Not only that, you didn't even tell her _why_ I was going to do it!"

"As you have never told _me _why you wanted to end your relationship, I can see no feasible way of how I would have been able to tell _her_."

"Fine! You want to know the reason? Well, do you?" Leonard seemed to be demanding a response from me, but before I could tell him that I had very little interest in the reason, he answered his own question anyway. "I'm moving away from Pasadena."

"Don't be absurd. You can't 'move away'. You're my roommate."

"I need to go home, Sheldon. Some family crisis involving my sister and some gibbons."

"The ones she's working with to cure diabetes?"

"Yeah, she... It doesn't matter! The point is, you had no right to tell Penny that I was going to break up with her."

"Penny is a good friend of mine. She asked me directly if you had mentioned 'terminating your relationship' with her, and you _know _that I can't lie to anybody or keep a secret without developing nervous tics! If you were _my _friend, you wouldn't put me in _that_ situation."

"Okay, maybe you weren't the best person to confide in with a secret," Leonard admitted. I was about to open my mouth and announce my victory in the argument when he continued. "But then you shouldn't have been eavesdropping!"

"Look, it doesn't matter. The point is, I don't see why you moving away for a little while to deal with a family crisis means that you had to end your relationship with Penny."

"I don't know if or when I'll be coming back. That's why I had to end it. It wouldn't be fair to Penny. And you know, things haven't really been the same since we broke up and got back together last time."

"Yes, you're right. Penny deserves better."

"_Excuse me_? How can _you _be the judge of that?"

"I've simply been observing social protocol in situations like this. You haven't even mentioned the possibility of a long-distance relationship, which indicates that you're not really that bothered about a relationship with Penny. Again."

"Whatever you say, Sheldon! You're _always_ right, aren't you?" This confused me for a second. Leonard would not usually concede so easily. Oh, wait. I understood now.

"Sarcasm again?"

"_Yes_. Honestly, Sheldon, I don't know why I put up with you sometimes." Leonard stormed out of the flat. This did not concern me. When he had done this on previous occasions, he visited Penny's flat. Other social protocols and norms indicated that this was no longer a possibility. I was right. Within three minutes, he had returned. I hypothesized that he would have been back sooner except his pride had prevented him from doing so.

"Oh, and by the way Leonard, I already knew that you knew that I informed Penny so that she knew of your intentions. I found it difficult to sleep last night with all the screaming and the shouting, ergo I heard everything that was said. Therefore, most of our earlier conversation was irrelevant."

For a moment, I didn't think Leonard would respond. I was wrong. "Why do you care about Penny so much all of a sudden? When I asked you to lie, or make an omission, in the past, you always went to great lengths to try and make it as believable as possible. Why couldn't you have done that when Penny asked you if I wanted to break up with her?"

"Believe me, I've been asking myself the same question," I muttered to myself.

"What was that?"

"Nothing. It doesn't matter." It seemed that we were at an impasse.

"Well," said Leonard eventually. "I'd better go and pack my suitcases."

"That would be logical, given that a working teleport has not been invented yet."

After Leonard had disappeared into his room, I had a little while to ponder. It had taken me years to finally commit to a 'dating' relationship with a woman, albeit a platonic one with Amy Farrah Fowler, but now I found myself torn between Penny and Amy. If I 'loved' Penny, did that mean that I couldn't love Amy? Or vice versa? It was a matter of fact that I found it a lot easier to initiate physical contact with Penny rather than Amy, but was that love or was it lust?

I couldn't love Penny, could I? The guys had frequently remarked that I was incapable of such feelings, and I was pretty certain that Penny had no romantic feelings towards me whatsoever.

The only person whom I felt was intelligent enough to help me with this dilemma was Amy, but I'd learned that social protocol indicated that this wouldn't be acceptable. It seemed that I only had once choice; whilst Leonard was busy, I would have to go and speak to Penny.


	3. Chapter 3

_Knock-knock-knock._

"Penny."

_Knock-knock-knock._

"Penny."

_Knock-knock-knock._

"Penny."

As ever, Penny humoured me and refrained from opening her apartment door until I had finished my compulsory _knock-knock-knock _routine. However, when it opened to reveal a visibly upset Penny, I was perturbed. "Is now a bad time? Should I come back later?" I enquired purely out of politeness, as social protocol dictated I should, but knew that I would be even more disconcerted if she said 'yes'. I had especially altered my routine to accommodate this unforeseen dilemma, and would not have been particularly happy if all the extra effort had been in vain.

"No, it's fine Sheldon, come on in." Penny sighed, stepping back to allow me entry to her apartment. "I've just split up with Leonard. Again. There's not going to be a 'good' time to disturb me for a while."

I stepped inside and she closed the door behind me quickly, as if she feared that Leonard would exit our apartment at the exact same moment that I entered hers, and that he would get the wrong impression. "I was only asking to be polite. I would have come in anyway, regardless of your answer."

Penny rolled her eyes and collapsed onto the sofa. "What's troubling you, Sheldon?" She made a feeble attempt to scrutinize my face, looking for clues. I was not so naive as to make my romantic feelings plain, after I had spent so long denying that I could feel them at all. "This isn't because you told me what Leonard was planning to do, is it? Has he been giving you a hard time? He has, hasn't he?" Penny sounded incredulous, which I thought was a little presumptuous as I hadn't even confirmed her suspicions. "That man has no right to take it out on you! What's happened is _his _fault, not yours."

I belatedly noticed that Penny was acting in my favour, choosing to defend me over the man with whom she had shared coitus. My newfound feelings must have been slowing my cognitive processing, or I would have realised this earlier. After all, Penny was not exceptionally intelligent, whereas I was. I had remarked once that this cognitive impairment had affected Leonard during one of his short-lived romantic relationships with a woman whom he had shared coitus on a regular basis. I had never shared coitus with anybody - anybody following me on Twitter would have been aware of this, alongside my friends and colleagues - but maybe the principle was the same, that relationships caused people to lose a little bit of themselves, whether it be their intelligence or their independence. In my case, I would be a piece of my dignity, after asserting for many years that I had no urge to have a romantic relationship with anyone or anything.

Before I could become lost in my own hypothesizing - I was currently torn between two theories; the first being that Penny's defensive stance in my favour was a sure sign of affection, and the second being that she was simply extremely annoyed at Leonard, with the stage in her current menstruation cycle not helping - I shook my head to dismiss my thoughts. Both situations were plausible, and therefore it was not helpful to dwell on them because without more evidence, the true explanation would remain elusive. "No. For once, my troubles are not of Leonard's design." Penny raised an eyebrow. Maybe my syntax _had _been a little confusing for her. I reluctantly rephrased to aid her understanding. "It's not Leonard who's bothering me."

Penny raised an eyebrow. "Who is it then?"

"You."

She rolled her eyes and moved to reopen the door. "Get out. I'm having enough of a hard time right now without listening to you explain how I've somehow upset you. What did I do, leave a hair on your bed when I sat on it the other day, or something equally as trivial as that?"

I didn't move. "I'm sorry, I shall rephrase again. You are bothering me because there is something about you that I don't understand."

"Are you saying that the great Sheldon Cooper has finally found something that he doesn't understand? That I, a community college drop-out, has somehow managed to baffle a man with an IQ of 187?" drawled Penny.

"Sarcasm?"

"Just a little bit."

"What about that time? Was _that _sarcasm?"

"It's irrelevant, Sheldon! What have I supposedly done to you, then? I'm waiting with bated breath."

I eyed her warily, still not convinced that she was telling me the truth, but decided to move on and deal with the more important - no, more _alarming _- matters so that I could leave and continue with my laundry. "Thoughts of you are occupying my mind at an increasingly alarming rate."

"Excuse me?" Penny looked bemused.

"You're excused. If _I_ don't understand why this is happening, then it's hardly fair of me to expect _you _to."

"I didn't mean 'excuse me' like that, as if I've done something wrong that I need to be forgiven for. I meant it in more of a 'has-somebody-slipped-something-into-Sheldon's-milk-again' way."

"Oh, I wish that it was that simple, Penny."

"What are you talking about, Sheldon? Either start making sense, or get out. I'm tired."

"You know very well what I'm talking about. It can't have slipped your notice that I tolerate more of your irritating behaviours than I do with Leonard, Howard or Raj. On more than one occasion, I've abandoned what I was doing in order to come to your aid. However, I realise that these aren't very scientific observations, and so I've taken the liberty of performing an experiment on myself to prove my point."

It was a few seconds before Penny could muster herself to speak. This revelation was evidently coming as a shock to both of us. "What kind of experiment?" Penny eyed me wearily.

"Well, I've noticed that every time I think of you, my blood pressure and heart rate become elevated. Therefore, if you would agree to monitor these measurements over the next few minutes, I will be able to tell you if you are the _cause _of these increased rates, or if it is simply correlational." I produced a sphygmomanometer for Penny to use. I could measure my heart rate myself, allowing for the possibility that erroneous measurements can occur when participants in a study attempt to self-measure.

"What happens if it's correlational?"

"Then further research will definitely be required, because these symptoms could be indicative of any number of illnesses, some serious and some not, but at the minute, I believe the most logical cause to be a new form of attachment or bond that I have inadvertently formed with you."

It was blatantly obvious that Penny didn't believe a word I was saying. "Okay, sweetie. If I go along with whatever this is, will you leave me alone for a little while? I just need some space Sheldon, because this situation with Leonard has really hurt me. Again."

"Agreed." I held out the sphygmomanometer for Penny to record my blood pressure, and I set about recording my own heart rate. I was intelligent enough to allow for the minimal error that would have been caused by measuring it in this way. After we had both finished recording our readings, I needed to see them in order to compare them with those that I would expect to see when I was not under the influence of Penny, or any other extraneous variables. "Show me."

Penny complied, and I was shocked to realise that the findings did indeed indicate cause and effect, not just a correlation. _Penny_ was causing _my _heart rate to accelerate, and blood pressure to rise. I suppose that I should have been mildly reassured and comforted that this meant that I did not have any serious illness, which would present with these symptoms. The reality of the situation however, was much more daunting. _I was attracted to Penny. And she didn't even know it. _All the physical symptoms were there. I would have asked Penny to confirm that my pupils had dilated, but I couldn't really rely on her answer being accurate, especially while she was in this particular emotional state.

"Sheldon, are you okay?" Penny was genuinely concerned for me, but I was more preoccupied in ascertaining that she hadn't really comprehended what I had said earlier. "What am I, a correlation or a cause?"

"Erm, correlation. I have to go." And with that lie I rushed out of Penny's apartment before the nervous ticks could start, startled by the revelation that I was attracted to Penny and she still blatantly believed it to be one of my quirks.

I was so preoccupied by my latest discovery, and the fact that I had proven it scientifically, that there were two things at the time that I failed to notice. The first was that Leonard was coming down the staircase from the floor above both Penny's apartment and ours, and consequently saw me leaving in a fluster that had been caused by the woman he purported to love. The second was that, in my haste to escape the truth, I missed Penny's final comment on our predicament as she looked in the mirror.

"I find it quite ironic that we were both so preoccupied by _his _heart rate and blood reassure that I've only just noticed that mine must have risen simultaneously when he entered the room in order for me to feel this restless. Oh great, my pupils are dilated and my face is flushing, too. _Where did all this come from all of a sudden_? I've only been single for twenty four hours!"

**Author's Note: Sorry for changing the title, and any confusion it may have caused. I'm happy with the title now, so I won't be changing it again! **


End file.
